Drawing scale



Jan. 18, 1949.

Filed Dec. 2, 1946 IH I I I l L! I l l I I I l I l I l r I I I I I l I l w 1 I/IIIIIIIIIIIIIII S. V. TOMKO DRAWING S GALE 2 Shets-Sheet 1 Inventor Stephen M. Tomko Attorneys Patented Jan. 18, 1949 UNITED STATES eATsNr OFFICE 3 Claims.

This invention relates to new and useful improvements in drawing scales and the primary feature of this invention is to provide a tape having various scale graduations along its outer edge thereby permitting said scale to be used for measurement in various systems of measurements.

Another feature voiithis invention is to provide a device of this character having scales of different systems and types opposite each other on the face of said tape, in a manner to make them the nearest equivalent to each other, this arrangement permitting quick conversion from one scale to another.

A further feature of this invention is to provide a tape of the character referred to having spool means at each end of said tape thereby affording means for winding the tape thereon to brin a selected scale into; position and for shipment or storing of said tape without marring its surface.

A still further feature of this invention is to provide a device of the character referred tothat is neat and attractive in appearance, efficient and reliable in operation, relatively inexpensive to manufacture and otherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a top plan view of the scale constructed in accordance with the present invention;

Figure 2 is a front elevation view thereof;

Figure 3 is a longitudinal sectional view taken on the line 3-3 of Figure 1;

Figure 4 is a sectional view taken on the line 4-4 of Figure 3;

Figure 5 is an end View of one of the spool housings taken in the direction of the line 55 of Figure 3, and

Figure 6 is a group perspective view of one of the spools with assembled parts removed therefrom.

Referring now to the drawings in detail, wherein for the purpose of illustration, I have disclosed a preferred embodiment of the invention, the numeral 5 represents a flexible tape having various types of scale graduations successively arranged on its upper face along its edges.

The ends 6 and l of tape 5 are adapted to extend upwardly as shown at 8 and 9 in the lower edges of a pair of spool housings l and II.

Ends 6 and 1 of tape fit into a pair of longi- 2 tudinal grooves I2 and HM in shafts 1-3 and 13a extending between the flanges of spools M and [4a respectively.

Bores l5 and key slots [5a extend longitudinally through the center of. shafts l3and I3a and said bores are adapted for receiving shafts t6 and liia having outwardly extending longitudinal keys ii and Ila engagedin the slots I511.

Suitably secured to one end of shafts ['5 and 56a are finger knobs l8 and 18a which are preferably circular having a pair ofkey openings 18b and tile and the opposite externally threaded ends l9 and Ma of said shafts are adapted to receive preferably circular nuts 20 and 20a having .20 pairs of key openings 21 and 121a which are adapted to receive the outer ends of substantially U-shaped keys .22, said key being. removable for also engaging openings fill) and l8c.

Transverse openings 23 are provided in housings l6 and II, said openings opposing the bores in the shafts 1'3 and l'ila of spools l4 and Ma :respectively, and recesses 24 and 24a are provided in the outer faces of said housings l8 and ill and around said openings 23, said recesses adapted to receive the finger knobs I8 and 18a and circular nuts 20 and 26a whereby the outer surfaces of the respective housings I0 and II are relatively smooth.

A substantially inverted T-shaped longitudinal arm 25 has its end suitably secured at 26 to the lower inner faces of housings Ill and II keeping said housings in spaced apart relation, said lower horizontal portions or flanges 21 of said arm 25 being slightly above the plane of the lower face of said housings and is adapted. to rest centrally on the upper surface of tape 5.

The side edges of said tape 5 extend outwardly from either side of said lower portions or flanges 21 as shown in Figure 1.

Said lower portions or flanges 21 are preferably transparent thereby permitting clear reading of the graduations on said tape which may extend under said lower portion.

The desired scales on tape 5 are brought into play by turning the finger knobs on shafts l6 and Ilia by key 22, which unwinds and winds the tape on spools l4 and Ma causing longitudinal movement of tape 5 under the lower portion 21 of arm 25.

The desired scale on tape 5 then rests flat against the work due to the weight of arm 25 thereon.

The scale on tape 5 is then held securely in place by tightening nuts 20 and Mo on the shafts If] and [3a by key 22, thereby preventing rotation of said shafts.

The tape is conveniently wound on one of said spools when shipment or storing of said device is desirable thereby keeping the tape in perfect condition for continual usage.

In View of the foregoing description taken in conjunction with the accompanying drawings it is believed that a clear understanding of the device will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention the same is susceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claims.

I claim:

1. A device of the class described comprising a pair of spool housings, a rigid arm extending between and connecting said housings in spaced apart relation to each other, a pair of spools journaled in said housings for rotation therein, and a graduated flexible tape carried by said spools and extending longitudinally under said connecting arm, the side edges of the tape projecting outwardly from each side of the arm.

2. A device of the class described comprising a pair of spool housings, an inverted T-shaped connecting arm, extending between said housings adapted to keep said housings in spaced apart relation, a pair of shafts journaled in said housings for rotation, a longitudinal key on said shafts, a pair of spools, longitudinal bores having key slots in said spools adapted to receive the shafts and the keys carried by said shafts, finger knobs carried by one end of said shafts, a substantially circular nut adjustably carried by the opposite ends of said shafts, said nuts being tightened against the housings for preventing rotation of said shafts, and a graduated flexible tape carried by said spools and adapted for longitudinal adjustment under said connecting arm, the lower portion of said connecting arm being transparent and bearing longitudinally on the upper face of said tape.

3. A device of the class described comprising a pair of spool housings, an inverted T-shaped connecting arm, extending between said housings adapted to keep said housings in spaced apart relation, a pair of shafts journaled in said housings for rotation, a longitudinal key on said shafts, a pair of spools, longitudinal bores having key slots in said spools adapted to receive the shafts and the keys carried by said shafts, finger knobs carried by one end of said shafts, a substantially circular nut adjustably carried by the opposite ends of said shafts, said nuts being tightened against the housings for preventing rotation of said shafts, recesses in the outer faces of said housings adapted toreceive said finger knobs and circular nuts carried by the shafts, and a graduated flexible tape carried by said spools and adapted for longitudinal adjustment under said connecting arm, the lower portion of said connecting arm being transparent and bearing on the upper face of said tape.

STEPHEN V. TOMKO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

